over the surface of, by way of, or within the limits or medium of: to travel through a country; to fly through the air.

during the whole period of; throughout: They worked through the night.

having reached the end of; done with: to be through one's work.

to and including: from 1900 through 1950.

by the means or instrumentality of; by the way or agency of: It was through him they found out.

by reason of or in consequence of: to run away through fear.

in at the first step of a process, treatment, or method of handling, passing through subsequent steps or stages in order, and finished, accepted, or out of the last step or stage: The body of a car passes through 147 stages on the production line. The new tax bill finally got through Congress.

adverb

in at one end, side, or surface and out at the other: to push a needle through; just passing through.

all the way; along the whole distance: This train goes through to Boston.

throughout: soaking wet through.

from the beginning to the end: to read a letter through.

to the end: to carry a matter through.

to a favorable or successful conclusion: He barely managed to pull through.

adjective

having completed an action, process, etc.; finished: Please be still until I'm through. When will you be through with school?

at the end of all relations or dealings: My sister insists she's through with selfish friends.

passing or extending from one end, side, or surface to the other: a through wound coming left to right and out the other side.

traveling or moving to a destination without changing of trains, planes, etc.: a through flight.

(of a road, route, way, course, etc., or of a ticket, routing order, etc.) admitting continuous or direct passage; having no interruption, obstruction, or hindrance: a through highway; through ticket.

(of a bridge truss) having a deck or decks within the depth of the structure.Compare deck(def 16).

of no further use or value; washed-up: Critics say he's through as a writer.

Idioms

through and through,

through the whole extent of; thoroughly: cold through and through.

from beginning to end; in all respects: an aristocrat through and through.

Origin of through

before 900;Middle English (preposition and adv.), metathetic variant of thourgh,Old Englishthurh, cognate with Germandurch; akin to Old Englishtherh,Gothicthairh through, Old High Germanderh perforated, Old Englishthyrel full of holes (adj.), hole (noun). See thirl